qemu/qemu_migration_params: use virStringParseYesNo helper

A function virStringParseYesNo was added to convert
string 'yes' to true and 'no' to false, so use this
helper to replace 'STREQ(.*, \"yes\")' and
'STREQ(.*, \"no\")' as it allows us to drop several
repetitive if-then-else string->bool conversion blocks.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NMao Zhongyi <maozhongyi@cmss.chinamobile.com>
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>

src/qemu/qemu_migration_params.c

@@ -1319,12 +1319,7 @@ qemuMigrationParamsParse(xmlXPathContextPtr ctxt,
             break;
 
         case QEMU_MIGRATION_PARAM_TYPE_BOOL:
-            if (STREQ(value, "yes"))
-                pv->value.b = true;
-            else if (STREQ(value, "no"))
-                pv->value.b = false;
-            else
-                rc = -1;
+            rc = virStringParseYesNo(value, &pv->value.b);
             break;
 
         case QEMU_MIGRATION_PARAM_TYPE_STRING: